Monsoon 2023 ends with 'below-normal' rains with 6% shortfall, says IMD

Oct-Dec winter rains to be normal, according to IMD

Despite a looming El Nino, the 2023 southwest monsoon season ended today with rainfall deficit of just 5.6 per cent from normal as a positive Indian Ocean Dipole (IOD) and Madden Julian Oscillation (MJO) helped in countering the negative impact of El Nino, the India Meteorological Department (IMD) said.

From June 1 to September 30, India received a cumulative rainfall of about 821 millimetres, compared to a normal of 869 millimetres. This amounts to 94 per cent of the Long Period Average (LPA), close to IMD's forecast of 96 per cent with a model error of plus or minus 4 per cent.

The monsoon 2023 was thus classified as 'below normal' rains, the first in four years. Monsoon between 96-104 per cent of LPA is considered as normal, while rainfall between 90-95 per cent of the LPA is considered as below normal and rainfall between 104-110 per cent of the LPA is considered as excess and rainfall below 90 per cent of the LPA is considered as deficient.

 

IMD Director General Mrutyunjay Mohapatra stated in a virtual press conference that the impact of El Nino on the Indian monsoon in 2023 was among the lowest since 1901. He added that the monsoon began to withdraw from western Rajasthan on September 25 and is expected to be completed by October 15.

Going forward, Mohapatra noted that although El Nino would continue to be a factor until March 2024, the positive IOD would persist, thereby positively influencing weather patterns. Consequently, post-monsoon North-East rains over southern peninsular India, including Tamil Nadu, Puducherry, Coastal Andhra Pradesh, Rayalaseema, Kerala and South Interior Karnataka, are expected to be normal, ranging from 88 to 112 per cent of the LPA.

The IMD also forecasts normal to above-normal rainfall over many areas of northwest and south peninsular India. However, below-normal rainfall is likely in northeast India, east central India and some areas of northwest India.

In terms of agriculture, good rainfall between October and December, particularly in northern and central parts of India, should aid the early planting and growth of major rabi crops like wheat, mustard and chana. For October 2023 alone, below-normal rainfall is expected over most parts of India, although southern and northeastern regions may see above-normal rainfall.

A good rainfall in October to December period particularly over Northern and Central parts of India should vastly aid in early planting and growth of main rabi crops such as wheat, mustard and chana.

IMD also said that in October 2023 alone, the rainfall over most parts of India is likely to be below-normal.

However, many areas in south peninsular India, northeast India, and a few pockets in the northernmost region of the country are likely to experience above- normal rainfall.

Monthly rainfall over the country as a whole in October 2023 is most likely to be normal (85-115 per cent of LPA). The LPA for October is 75.4 millimeters.

Reflecting on the 2023 monsoon season, Mohapatra acknowledged the IMD's failure to accurately predict the record 36 per cent shortfall in August, adding that an analysis would be conducted to identify the reasons for this inaccuracy. Despite the August shortfall, rainfall rebounded sharply in September, driven by five Low Pressure Systems, thereby preserving the kharif harvest.

Region-wise, 73 per cent of India's 36 meteorological sub-divisions received normal rainfall, while 18 per cent experienced below-normal levels. Overall, apart from the August misforecast, the IMD said its monthly and seasonal cumulative predictions for 2023 were accurate.

Monsoon from June 1 to September 30 (final) in millimeters

Region	Actual	Normal	% Change
East and NE India	1115	1367.3	-18
North-West India	593	587.6	1
Central India	981.7	978	0
South Peninsula	659	716.2	-8
All India	820	868.9	-6

Source: India Metereological Department
Note: Percentages have been rounded off to the next decimal